The stack size adjustment for detecting stack overflow in threads was not
taking into account that the requested stack size could be <= 8k, in which
case the subtraction would overflow. This is fixed in this commit by
ensuring that the adjustment can't be more than the available size.
This fixes the test tests/thread/thread_stacksize1.py which sometimes
crashes with a segmentation fault because of an uncaught NLR jump, which is
a "maximum recursion depth exceeded" exception.
Suggested-by: @dpgeorge
This changes the signal used to trigger garbage collection from SIGUSR1 to
SIGRTMIN + 5. SIGUSR1 is quite common compared to SIGRTMIN (measured by
google search results) and is more likely to conflict with libraries that
may use the same signal.
POSIX specifies that there are at least 8 real-time signal so 5 was chosen
as a "random" number to further avoid potential conflict with libraries
that may use SIGRTMIN or SIGRTMAX.
Also, if we ever have a `usignal` module, it would be nice to leave SIGUSR1
and SIGUSR2 free for user programs.
This modifies the signature of mp_thread_set_state() to use
mp_state_thread_t* instead of void*. This matches the return type of
mp_thread_get_state(), which returns the same value.
`struct _mp_state_thread_t;` had to be moved before
`#include <mpthreadport.h>` since the stm32 port uses it in its
mpthreadport.h file.
One can't use pthread calls in a signal handler because they are not
async-signal-safe (see man signal-safety). Instead, sem_post can be used
to post from within a signal handler and this should be more efficient than
using a busy wait loop, waiting on a volatile variable.
Header files that are considered internal to the py core and should not
normally be included directly are:
py/nlr.h - internal nlr configuration and declarations
py/bc0.h - contains bytecode macro definitions
py/runtime0.h - contains basic runtime enums
Instead, the top-level header files to include are one of:
py/obj.h - includes runtime0.h and defines everything to use the
mp_obj_t type
py/runtime.h - includes mpstate.h and hence nlr.h, obj.h, runtime0.h,
and defines everything to use the general runtime support functions
Additional, specific headers (eg py/objlist.h) can be included if needed.
This is to keep the top-level directory clean, to make it clear what is
core and what is a port, and to allow the repository to grow with new ports
in a sustainable way.
Damien George